A. Field of the Invention
Among other things, the present invention is related to a spacer for surgical implant or a combination of a first spinal device, a second spinal device and a spacer. Inclusion of the spacer between the first spinal device and the second spinal device allows the spinal column to be distracted a greater length than the length of the two spinal devices.
B. Description of the Previous Art
Any discussion of references cited in this Description of the Previous Art merely summarizes the disclosures of the cited references and Applicant makes no admission that any cited reference or portion thereof is relevant prior art. Applicant reserves the right to challenge the accuracy, relevancy and veracity of the cited references.
U.S. Pat. No. 6,863,673—Gerbec, et al., U.S. Pat. No. 6,852,129—Gerbec, et al., U.S. Pat. No. 6,562,074—Gerbec, et al. and U.S. Pat. No. 6,648,917—Gerbec, et al. disclose adjustable bone fusion implants and methods. U.S. Pat. No. 6,863,673—Gerbec, et al., U.S. Pat. No. 6,852,129—Gerbec, et al., U.S. Pat. No. 6,562,074—Gerbec, et al. claim a chain of priority to U.S. Pat. No. 6,648,917—Gerbec, et al. U.S. Pat. No. 6,863,673—Gerbec, et al. is illustrative of the disclosures of each of the Gerbec, et al. Patents.
By way of example, U.S. Pat. No. 6,863,673—Gerbec, et al., in part reads, “As depicted in FIG. 5A, reinforcing member 16 is in the form of a substantially U-shaped clip. Specifically, reinforcing member 16 comprises a substantially U-shaped cantilever beam 124 which includes an elongated base 126 having supports 128 and 130 upstanding from each opposing end thereof. Forwardly projecting from the top end of support 128 and 130 is an elongated flexible arm 132 and 134, respectively. Each arm 132 and 134 terminates at a free end 136 having an inwardly facing latching barb 138 formed thereat. Each latching barb 138 has a sloped forward surface 140 and an orthogonally disposed inside surface 142. Reinforcing member 16 has a width extending between the outside of opposing arms 132 and 134 that is substantially the same as the maximum width of cap 12 and base 14.
Once cap 12 is selectively elevated relative to base 14, a gap 146 is formed between cap plate 18 and each biasing rail 111 and 112. Reinforcing member 16 is configured such that each arm 132 and 134 can be slidably received within a corresponding gap 146 on each side of housing 11. Sloping surface 140 on each latching barb 138 biases against support members 48-51 and/or the threads thereon causing arms 132, 134 and/or cantilever beam 124 to outwardly bend, thereby enabling latching barbs 138 to pass over support members 48-51. As latching barbs 138 pass over support members 50 and 51, the resilient flexing of arms 132, 134 causes latching barbs 138 to inwardly bias and catch behind support members 50 and 51. The engagement of flat inside surface 142 of each latching barb 138 against the flat side of support members 50 and 51 prevents reinforcing member 116 from unintentionally disconnecting with housing 15. However, in one embodiment arms 132 and 134 are sufficiently flexible that reinforcing member 16 can be removed from housing 11 by simply pulling back on cantilever beam 124. In this regard, reinforcing member 16 is removably positioned. In the assembled configuration shown in FIG. 5B, reinforcing member 16 is positioned between cap plate 18 and base plate 70. More specifically, any compressive force 122 applied to the assembled fusion implant 10 causes arms 132 and 134 of reinforcing member 16 to be compressed between cap plate 18 and biasing rails 111 and 112. As a result, the compressive load is carried primarily through reinforcing member 16 as opposed to through interlocking teeth 60 and 100. In such configuration, some embodiments of fusion implant 10 are capable of withstanding over 2,000 pounds of compressive force without failure or permanent deformation.
As previously discussed, gap size 146 can be selectively incrementally increased by adjusting which teeth 60 and 100 are meshed together. In one embodiment, a discrete reinforcing member is provided for each gap size 146. For example, depicted in FIGS. 5A and 5B, reinforcing member 16 is configured to be received within gap 146 so as to produce a relatively close tolerance. Depicted in FIGS. 6A and 6B, a gap 150 is formed between cap plate 18 and biasing rails 111 and 112. Gap 150 has a height greater than the height of gap 146. For example, gap 146 may correspond to a single tooth spacing while gap 150 corresponds to a spacing of two or more teeth. As such, a reinforcing member 152 is provided. Although reinforcing member 152 has the same structural elements as reinforcing member 16, arms 132 and 134 thereof have an increased height so as to selectively receive within gap 150 under a relatively close tolerance. It is appreciated that a plurality of reinforcing members can be provided with each reinforcing member being configured to fit a different sized gap formed between cap plate 18 and biasing rails 111 and 112. In an alternative embodiment, it is also appreciated that instead of using a larger reinforcing member, a plurality of smaller reinforcing members can be used to fill a single gap. This configuration minimizes the requirement of having to maintain a number of different sizes of reinforcing members.
As depicted in FIGS. 5B and 6B, the purpose of using U-shaped cantilever beam 124 is that beam 124 only covers a portion of access mouth 116. An opening 154 remains that provides communication with compartment 8. As discussed below, opening 154 can be used for feeding bone graft into compartment 8.
Depicted in FIG. 6C is an alternative embodiment of a reinforcing member 197. Reinforcing member 197 comprises a face plate 198 having arms 132 and 134, as previously discussed, projecting therefrom. In one embodiment of the present invention, means are provided for removably connecting an insertion tool to reinforcing member 197. By way of example and not by limitation, a threaded aperture 199 extends through face plate 198. As will be discussed below in greater detail, threaded aperture 199 enable a tubular insertion tool to be threadedly engaged to aperture 199. The bone graft can then be passed down through the tubular insertion tool and into compartment 8. Examples of alternative embodiments of the means for removably connecting an insertion tool to reinforcing member 197 include the same alternatives as previously discussed with regard to the means for removably connecting an insertion tool to attachment wall 68. Each of the components of fusion implant 10 is made from a medical grade biocompatible material. In one embodiment, the components are molded from a carbon fiber reinforced polyetheretherketone polymer. In alternative embodiments, the components can be molded, cut, machined, or otherwise formed from medical grade biocompatible metals, polymers, ceramics, or other materials that have adequate strength. It is also appreciated that different components can be made from different materials. For example, the reinforcing member can be made of metal while the remainder is formed from a plastic. Although fusion implant 10 can be used for fusing together a variety of different bone matter together, illustrated below for purposes of example is one method of using fusion implant 10 for fusing together adjacent vertebrae in a spine. Specifically, depicted in FIG. 7A is a pair of adjacent vertebrae 156 and 158. A posterior opening has been made through the back of the person so as to expose vertebrae 156 and 158. A disk or portion of a disk has been removed from between vertebrae 156 and 158 so that a gap 160 is formed therebetween. Because of the select vertebrae, gap 160 is wedged shaped having a wider portion that faces anteriorly towards the front of a patient and is narrower posteriorly towards the back of the patient.
To optimize fusing of vertebrae 156 and 158 while minimizing post-operative complications, a wedged shaped fusion implant having a size substantially corresponding to gap 160 should be inserted within gap 160. Because gap 160 narrows posteriorly, conventional procedures have required that if a wedged shaped implant was to be inserted within gap 160, it would have to be inserted anteriorly through the front of the patient. Inserting through the front of the patient, however, significantly complicates the procedures in that it requires the surgeon to navigate around a number organs and blood vessels. The other conventional option was to insert a flat, i.e., non-wedged shaped, fusion implant posteriorly into gap 160. Since the fusion implant was flat, however, it would not properly fit gap 160, thereby raising the specter of potential post-operative complications. As discussed below, the present invention enables the posterior insertion of a wedged shaped fusion implant into gap 160, thereby optimizing the benefits. Of course, in alternative uses the applicable gap may not be wedged shaped. The fusion implant thus need not be wedged shaped but can be shaped according to its intended use.”
Among other things, it does not appear that the Gerbec invention practices, “A spinal implant inserted about a surgically created cavity proximate to one or more vertebrae; said spinal implant comprising: a) a biocompatible cage comprising: i) a length having a central longitudinal axis and a plurality of sides, wherein at least some of said sides comprise a plurality of openings surrounding a channel; said openings capable of exposing osteogenic substances to said surgically created cavity; and ii) a first end perimeter comprising an open entry into said channel; b) an end cap comprising: i) a border facing said biocompatible cage; ii) a plate extending in a lengthwise direction, parallel said central longitudinal axis, away from said border and comprising at least one opening capable of receiving a fastener; and iii) a pair of opposed docking slides extending from said border toward said biocompatible cage; said docking slides adapted to engage inward sides of said biocompatible cage, wherein said docking slides' surfaces engaging said inward sides of said biocompatible cage are without surface areas adapted for impeding removal of said docking slides from said biocompatible cage; and c) a spacer adapted for allowing adjustment of length of said spinal implant and sandwiched between said biocompatible cage and said end cap; said spacer comprising: i) a first leg extending toward the inward side of said spinal implant; ii) a second leg opposed from said first leg and extending toward the inward side of said spinal implant; and iii) an anterior section anterior to said plate; said anterior section sharing a margin with outward ends of said first and said second legs and extending in a lengthwise direction parallel said central longitudinal axis.”
Among other things, it does not appear that the Gerbec invention practices, “A combination comprising a spacer positioned between a surgically implanted first spinal device and a surgically implanted second spinal device, wherein said first and said second spinal devices include a common longitudinal axis; said spacer comprising: a) a first leg sandwiched between said first and said second spinal devices, wherein said first leg comprises a first side comprising apertures adapted to engage some of a plurality of spikes extending, parallel said longitudinal axis, from one of said spinal devices; b) a second leg sandwiched between said first and said second spinal devices, wherein said second leg comprises a first side comprising apertures adapted to engage some of said spikes extending, parallel said longitudinal axis, from said one of said spinal devices; and c) an anterior section anterior to said first and said second spinal devices and connected with an outward end of said first leg and an outward end of said second leg.”
U.S. Pat. No. 6,641,614—Wagner et al. discloses a multi-variable-height fusion device. Wagner, in part, reads, “An alternate embodiment of an interbody fusion device is depicted in FIGS. 25-27. FIG. 25 is a perspective view of the fusion device in a lowered position. FIG. 26 is a perspective view of the fusion device in a raised position. FIG. 27 is an exploded view of the fusion device. Fusion device 200 includes a pair of engaging plates 202 and 204 for engaging adjacent vertebrae. Engaging plates 202 and 204 are preferably separated by bracket assembly 206. Engaging plates 202 and 204 and bracket assembly 206 may be formed of titanium, stainless steel, polymer, ceramic, composite material, or any other biocompatible material. For purposes of this description, “biocompatible material” is material not rejected by the body and/or not causing infection following implantation.
As depicted in FIG. 27, engaging plates 202 and 204 may contain a plurality of protrusions 216 from outer surfaces 203 for enhancing an engagement between the vertebrae and the engaging plates. In this manner, subsidence of the vertebrae may be substantially prevented as previously described. Outer surfaces 203 are preferably substantially planar to provide a large contact area between the engaging plates and the vertebrae; alternately, outer surfaces 203 may be non-planar. Protrusions 216 may extend into the vertebrae to prevent the fusion device from moving out of the disc space. Engaging plates 202 and 204 may include a plurality of openings 218 to allow bone development and growth through the engaging plates and between fusion device 200 and the neighboring vertebrae. In an embodiment, openings 218 have a combined area that is greater than about 50% of the total area of outer surfaces 203 (including the area of openings 218). More preferably, openings 218 have a total area between 60% and 80% of the total area of outer surfaces 203. More preferably still, openings 218 have a total area of 70% or more of the total area of outer surfaces 203.”
Among other things, it does not appear that the Wagner invention practices, “A spinal implant inserted about a surgically created cavity proximate to one or more vertebrae; said spinal implant comprising: a) a biocompatible cage comprising: i) a length having a central longitudinal axis and a plurality of sides, wherein at least some of said sides comprise a plurality of openings surrounding a channel; said openings capable of exposing osteogenic substances to said surgically created cavity; and ii) a first end perimeter comprising an open entry into said channel; b) an end cap comprising: i) a border facing said biocompatible cage; ii) a plate extending in a lengthwise direction, parallel said central longitudinal axis, away from said border and comprising at least one extending from said border toward said biocompatible cage; said docking slides adapted to engage inward sides of said biocompatible cage, wherein said docking slides' surfaces engaging said inward sides of said biocompatible cage are without surface areas adapted for impeding removal of said docking slides from said biocompatible cage; and c) a spacer adapted for allowing adjustment of length of said spinal implant and sandwiched between said biocompatible cage and said end cap; said spacer comprising: i) a first leg extending toward the inward side of said spinal implant; ii) a second leg opposed from said first leg and extending toward the inward side of said spinal implant; and iii) an anterior section anterior to said plate; said anterior section sharing a margin with outward ends of said first and said second legs and extending in a lengthwise direction parallel said central longitudinal axis.”
Among other things, it does not appear that the Wagner invention practices, “A combination comprising a spacer positioned between a surgically implanted first spinal device and a surgically implanted second spinal device, wherein said first and said second spinal devices include a common longitudinal axis; said spacer comprising: a) a first leg sandwiched between said first and said second spinal devices, wherein said first leg comprises a first side comprising apertures adapted to engage some of a plurality of spikes extending, parallel said longitudinal axis, from one of said spinal devices; b) a second leg sandwiched between said first and said second spinal devices, wherein said second leg comprises a first side comprising apertures adapted to engage some of said spikes extending, parallel said longitudinal axis, from said one of said spinal devices; and c) an anterior section anterior to said first and said second spinal devices and connected with an outward end of said first leg and an outward end of said second leg.”